<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title></title>
    <style media="screen">
      .bg{
        background: red;
      }
    </style>
  </head>
  <body>
    <button type="button" name="button">click me!</button>
    <script type="text/javascript" src="ui.js">


    </script>

  </body>
</html>
